OBJECTIVES: 1. To determine the abilities of the chimpanzee for the mastery of selected language-type skills and functions. 2. To determine the potential value of the chimpanzee as an animal model for linguistic research projects as to the parameters of initial language skills which cannot be conducted with children because of ethical constraints. 3. To explore the value of the computer-based language-training system, devised for the above projects, for research into problems of language learning by mentally retarded children. BIBLIOGRAPHIC REFERENCES: Rumbaugh, D. M. The learning and symbolizing capacities of apes and monkeys. In Russell H. Tuttle (Ed.), Socioecology and psychology of primates. The Hague: Mouton Publishers, 1975, pp. 353-365. Warner, H., Bell, C. L., Rumbaugh, D. M., and Gill, T. V. Computer-controlled teaching instrumentation for linguistic studies with great apes. IEEE Transactions on Computers, 1976, 25, 38-43.